In the process automation industries, it is common to have processes that are hazardous. In order to prevent accidents caused by equipment faults, independent agencies certify equipment as intrinsically safe (IS). The premise of this certification is that under no conditions could an equipment fault occur that would discharge enough energy to ignite a hazardous gas, dust or liquid. As battery technologies advance, battery cells are capable of storing increasing amounts of energy in the same package size. This creates a dichotomy for portable, battery powered, intrinsically safe equipment. One of the tests certification agencies use to approve batteries is the short circuiting of the battery and measurement of its surface temperature. There are various temperature classifications, but no spot on the battery surface can exceed the limit of the classification. For example, a T4 classification has a limit of 130 degrees C. Modern batteries typically fail this test and exceed the maximum permitted temperature for the T4 classification.
A method and apparatus are needed to adapt energy storage cells and batteries for use in hazardous industrial locations where intrinsic safety standards must be met.